Added Post system. Notification system

src/main/java/site/easystartup/web/exception/NoPermissionException.java

@@ -1,5 +1,9 @@
 package site.easystartup.web.exception;
 
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.ResponseStatus;
+
+@ResponseStatus(HttpStatus.FORBIDDEN)
 public class NoPermissionException extends RuntimeException {
     public NoPermissionException(String username) {
         super("User " + username + " do not have access for this action");